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Amperage, Voltage & Wattage

Aug 6, 2012 10:00 PM

Tags: #ups #power_supply #wattage #amperage #voltage #apc

Let me start by saying that I am in the telecommunications business. I have been for well over 30 years if I count the US Army. Currently, I provision and install routers in customer locations, among other tasks. Each and every router I install gets its own UPS, unless the customer has the entire room, or the rack protected. Let me also say I have had quite a few electronics classes. And even taught some. That didn't stop me from doing something stupid.

 

We install 550A APC brand UPS at work.  At Costco, I get 500A for the house. I have quite a few. I have been doing that for years. I used to live in Texas and Florida. Both have terrible lightening and quite often have brown outs and power outages. So a UPS saves me from various problems.

 

So, now I am going to tell an embarrassing story on myself, on the off chance that it keeps someone else from suffering.

 

On Saturday I was using Premiere Pro to export a 30 minute video using a Vimeo 1080P preset. I heard the case fan kick in and I opened the Resource Monitor. Wow! So cool!  All 12 CPU graphs showed 100% of capacity. Premiere Pro was using over 21G of RAM. I have never had more than 4G before. So cool! I was delighted. Everything was just screaming along. The only hard drive working hard was where the media is stored, but it is a RAID0 so it is reasonably quick - only hit max now and then.

 

My wife came in and asked a question. I thought, "What the heck? What could it hurt? I would steal a few CPU cycles and open a browser for a moment, get her answer and be the good husband."

 

I opened Chrome, started to type my question and "POOF!". No power. Black screen. No fan noise. No Power light on the brand new PC!!! Nothing. OH! MY! GOD!!

 

What to do? I tried turning it back on. Nope. Waited a couple of minutes. It turned on then it died in a second.  OK, I figured it was overheated. Or the power supply was faulty. In any case, something was terribly wrong. I waited two hours, turned it on, and continued using the PC - but I didn't try that particular export again.

 

I drafted an e-mail for Eric at ADK asking for assistance. I proceeded to use the PC all weekend, even exported a short video, but nothing that would run flat out for more than a minute or two. Not the 90 minutes I need to export that particular video again.

 

So, Eric gets in to work and gets around to my e-mail reasonably quick. He gives me a call as requested. I relate the story even though he read the e-mail, hoping I could provide more information.

 

Eric proceeds to calmly ask what I have the PC plugged into. I proudly say a UPS of course. He asks what brand and model. OK, I'll bite. I crawl under the desk and tell him it is a 550A APC. I turn it over and read the label. It is 550A and 330 Watts. Wait a minute! 330 Watts? Eric installed an 850 Watt Power Supply in my new PC.  Holy Moley!

 

Eric was quite polite. He refrained from laughing at me. Nice guy. Probably because I was beating myself up pretty good as it was. He didn't need to. In fact, I have been beating myself up about it all day. He did remind me that they tested my PC at 100% of capacity when they built it and that heat should not be a problem even at full capacity with the cooling system they installed.

 

A little research indicates that some 1500A UPS can handle 900 Watts at 120 Volts, while some can handle 1000 Watts. These things are expensive, by the way! I figure that ordering a 1500A UPS from Costco might be the way to go. But I will check all of the stores around here first. I would like to avoid plugging the PC directly into the wall. That of course, would solve the immediate problem, but I can't bring myself to do it.

 

So, if you find yourself upgrading, don't forget to check your UPS. In the meantime, I am so grateful that it wasn't my new PC. Just a problem between the keyboard and the chair.

 

-- Steven

 
Replies
  • Currently Being Moderated
    Aug 6, 2012 11:00 PM   in reply to Steven L. Gotz

    Steven,

     

    Thanks for sharing your experiences. I think it will help many people from falling into the same trap.

     

    I often advise people to have a look at eXtreme Power Supply Calculator Pro v2.5 when they want to know what kind of PSU they will probably need, but the great thing about this calculator is that it also gives you the suggested UPS rating. In my case it suggests 2200 VA. You can find the screenshot for my system here Planning & Building a NLE System under the tab 'Disks, PSU' in the first topic.

     

    Luckily the electricity net here is quite reliable. My own UPS for the server, also an APC, has the battery replaced as often as brown outs. Once in about 5 years, so I think the cost of an UPS for my workstation, that is expensive enough for my taste, is more a luxury question than pure necessity. But the US with all their wooden poles and above ground electricity cables and sometimes extreme weather is much more susceptible to power outages than here, so your advise and story is very worthwhile.

     

    PS. Depending on the reliability of the electricity net and the availability of a backup generator, you may also want to look at additional batteries in the UPS to extend the run time.

     

    UPS-runtime.png

    Notice the difference between lines A and B in run time by a simple addition of an extra battery. Admitted, it is a logarithmic scale, but still.

     
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  • Currently Being Moderated
    Aug 7, 2012 12:46 AM   in reply to Steven L. Gotz

    That is a different price category than I mentioned above. The APC 2200 VA tower/5u UPS-XL is € 840 and the extended run time battery is € 610 here, excluding 19% VAT and excluding transport. The UPS alone has a shipping weight of 80 kg. See the specs http://www.apc.com/resource/include/techspec_index.cfm?base_sku=sua220 0xli

     

    The system you are building (have built?) is truly a monster.

     

    I have to agree with that, but take into consideration what I said on the price tag tab:

     

    * I warned you that the case will be considered exorbitant by many. It is way more expensive than a regular mid-tower or even a big-tower, up to 10 times the price (including the shipping costs). But keep in mind that a case has an almost everlasting life. It is similar to a tripod that outlives a camera many times. I'm pretty confident that I can still use this case when the third generation i9 CPU's with 32 cores plus Hyper Threading with support for 256+ GB memory are available, or even dual 40-core Xeons with up to 1 TB memory. I consider this a long term investment.

     

    I'm still waiting for the following reasons:

    It may be in vain, but while the build progresses and I decide on more and more components, I am hoping that Intel will come out with an Ivy Bridge-E CPU, based on the 22nm production process, that will have all 8 cores and the full complement of 20 MB L3 cache enabled and still remain within the Intel TDP limits.

     

    Rumors are that Intel will introduce the i7-3970X in Q4, still based on the 32 nm (Sandy Bridge-E) technology, but with a base clock of 3.5 GHz and a turbo boost at 4.0 GHz for the same price as the current i7-3960X, whose price will be reduced at that time. It will still be a hexa core chip with 15 MB L3 cache, but will run 200 MHz faster than the i7-3960X. The TDP of the new chip will be 150W.

    In the meantime I am just biting my nails. Well, Rome wasn't built in one day either.

     

    The second reason I have for postponing on this section is that I hope Areca will shortly announce a new range of raid cards that support PCIe-3.0 instead of the current 2.0 versions. The latest news from Areca mentions that the new SAS 6Gb RAID card with PCIe-3.0 interface should be available around Q3 this year. Whether that means July 1 or September 30, I do not know.

     

    Did you recently marry off a daughter into the Royal Family of the Netherlands?

     

    No, I did not because I'm already married (for nearly 35 years now) and if I were available, I would probably prefer Pippa Middleton, even though Karl Lagerfield does not agree with me on this choice.

     
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  • Currently Being Moderated
    Aug 7, 2012 8:33 AM   in reply to Steven L. Gotz

    LOL. No. I asked if you married off your daughter!  Not if you married a Royal!  :-)

     

    My mistake, but no my daughter is engaged to a Swiss guy and of all the princes we have here (they are all married BTW), Maurits is her/my favorite. He is a swell guy with whom I have worked and sailed with before, but the other princes are equally nice. When you get into their circle it is surprising to notice they are so common, so empathic, so enthousiastic, so nice and no sign of grand-standing at all.

     
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    Aug 12, 2012 6:35 AM   in reply to Steven L. Gotz

    Steven, do a export like our PPBM5.5 MPEG2-DVD sequence with the MPE software only and you will see 100% or near it quite a bit.  That is why we have the GPU's

     
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  • Currently Being Moderated
    Aug 13, 2012 11:42 AM   in reply to Steven L. Gotz

    With today's Line Interactive UPS designs you cannot go by the operational load of the gear or systems. You have to go by the Initialization load of the system which will be the full rating of the PSU until all the circuits initialize. The mantra that the operational load is all you need to worry about is what gets people into trouble. That worked in the old days when you had Stand By Design UPS units. That does not work in the Line Interactive design. If you dont have enough load available then the system will not initialize correctly and the issues will be all over the place. Eventually you will blow your PSU and likely other components. I have seen this to often lately and have had clients call me with a system almost wiped out because of this. I highly recommend people go by the Rated value of the PSU in the system and buy a UPS greater than that. If not then DONT get a UPS. Get a power modulator or surge protector.

     

    Eric

    ADK

     
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